blob: 962f2fdb378c4dfd0ce52b61cb23368851cb772f [file] [log] [blame]
/* GStreamer
* Copyright (C) 1999,2000 Erik Walthinsen <omega@cse.ogi.edu>
* 2000 Wim Taymans <wtay@chello.be>
*
* gstpad.c: Pads for linking elements together
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Library General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Library General Public License for more details.
*
* You should have received a copy of the GNU Library General Public
* License along with this library; if not, write to the
* Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
* Boston, MA 02110-1301, USA.
*/
/**
* SECTION:gstpad
* @short_description: Object contained by elements that allows links to
* other elements
* @see_also: #GstPadTemplate, #GstElement, #GstEvent, #GstQuery, #GstBuffer
*
* A #GstElement is linked to other elements via "pads", which are extremely
* light-weight generic link points.
*
* Pads have a #GstPadDirection, source pads produce data, sink pads consume
* data.
*
* Pads are typically created from a #GstPadTemplate with
* gst_pad_new_from_template() and are then added to a #GstElement. This usually
* happens when the element is created but it can also happen dynamically based
* on the data that the element is processing or based on the pads that the
* application requests.
*
* Pads without pad templates can be created with gst_pad_new(),
* which takes a direction and a name as an argument. If the name is %NULL,
* then a guaranteed unique name will be assigned to it.
*
* A #GstElement creating a pad will typically use the various
* gst_pad_set_*_function() calls to register callbacks for events, queries or
* dataflow on the pads.
*
* gst_pad_get_parent() will retrieve the #GstElement that owns the pad.
*
* After two pads are retrieved from an element by gst_element_get_static_pad(),
* the pads can be linked with gst_pad_link(). (For quick links,
* you can also use gst_element_link(), which will make the obvious
* link for you if it's straightforward.). Pads can be unlinked again with
* gst_pad_unlink(). gst_pad_get_peer() can be used to check what the pad is
* linked to.
*
* Before dataflow is possible on the pads, they need to be activated with
* gst_pad_set_active().
*
* gst_pad_query() and gst_pad_peer_query() can be used to query various
* properties of the pad and the stream.
*
* To send a #GstEvent on a pad, use gst_pad_send_event() and
* gst_pad_push_event(). Some events will be sticky on the pad, meaning that
* after they pass on the pad they can be queried later with
* gst_pad_get_sticky_event() and gst_pad_sticky_events_foreach().
* gst_pad_get_current_caps() and gst_pad_has_current_caps() are convenience
* functions to query the current sticky CAPS event on a pad.
*
* GstElements will use gst_pad_push() and gst_pad_pull_range() to push out
* or pull in a buffer.
*
* The dataflow, events and queries that happen on a pad can be monitored with
* probes that can be installed with gst_pad_add_probe(). gst_pad_is_blocked()
* can be used to check if a block probe is installed on the pad.
* gst_pad_is_blocking() checks if the blocking probe is currently blocking the
* pad. gst_pad_remove_probe() is used to remove a previously installed probe
* and unblock blocking probes if any.
*
* Pad have an offset that can be retrieved with gst_pad_get_offset(). This
* offset will be applied to the running_time of all data passing over the pad.
* gst_pad_set_offset() can be used to change the offset.
*
* Convenience functions exist to start, pause and stop the task on a pad with
* gst_pad_start_task(), gst_pad_pause_task() and gst_pad_stop_task()
* respectively.
*/
#include "gst_private.h"
#include "gstpad.h"
#include "gstpadtemplate.h"
#include "gstenumtypes.h"
#include "gstutils.h"
#include "gstinfo.h"
#include "gsterror.h"
#include "gstvalue.h"
#include "glib-compat-private.h"
GST_DEBUG_CATEGORY_STATIC (debug_dataflow);
#define GST_CAT_DEFAULT GST_CAT_PADS
/* Pad signals and args */
enum
{
PAD_LINKED,
PAD_UNLINKED,
/* FILL ME */
LAST_SIGNAL
};
enum
{
PAD_PROP_0,
PAD_PROP_CAPS,
PAD_PROP_DIRECTION,
PAD_PROP_TEMPLATE,
PAD_PROP_OFFSET
/* FILL ME */
};
#define GST_PAD_GET_PRIVATE(obj) \
(G_TYPE_INSTANCE_GET_PRIVATE ((obj), GST_TYPE_PAD, GstPadPrivate))
/* we have a pending and an active event on the pad. On source pads only the
* active event is used. On sinkpads, events are copied to the pending entry and
* moved to the active event when the eventfunc returned %TRUE. */
typedef struct
{
gboolean received;
GstEvent *event;
} PadEvent;
struct _GstPadPrivate
{
guint events_cookie;
GArray *events;
guint last_cookie;
gint using;
guint probe_list_cookie;
guint probe_cookie;
/* counter of how many idle probes are running directly from the add_probe
* call. Used to block any data flowing in the pad while the idle callback
* Doesn't finish its work */
gint idle_running;
};
typedef struct
{
GHook hook;
guint cookie;
} GstProbe;
#define PROBE_COOKIE(h) (((GstProbe *)(h))->cookie)
#define GST_PAD_IS_RUNNING_IDLE_PROBE(p) \
(((GstPad *)(p))->priv->idle_running > 0)
typedef struct
{
GstPad *pad;
GstPadProbeInfo *info;
gboolean dropped;
gboolean pass;
gboolean marshalled;
guint cookie;
} ProbeMarshall;
static void gst_pad_dispose (GObject * object);
static void gst_pad_finalize (GObject * object);
static void gst_pad_set_property (GObject * object, guint prop_id,
const GValue * value, GParamSpec * pspec);
static void gst_pad_get_property (GObject * object, guint prop_id,
GValue * value, GParamSpec * pspec);
static void gst_pad_set_pad_template (GstPad * pad, GstPadTemplate * templ);
static gboolean gst_pad_activate_default (GstPad * pad, GstObject * parent);
static GstFlowReturn gst_pad_chain_list_default (GstPad * pad,
GstObject * parent, GstBufferList * list);
static GstFlowReturn gst_pad_send_event_unchecked (GstPad * pad,
GstEvent * event, GstPadProbeType type);
static GstFlowReturn gst_pad_push_event_unchecked (GstPad * pad,
GstEvent * event, GstPadProbeType type);
static guint gst_pad_signals[LAST_SIGNAL] = { 0 };
static GParamSpec *pspec_caps = NULL;
/* quarks for probe signals */
static GQuark buffer_quark;
static GQuark buffer_list_quark;
static GQuark event_quark;
typedef struct
{
const gint ret;
const gchar *name;
GQuark quark;
} GstFlowQuarks;
static GstFlowQuarks flow_quarks[] = {
{GST_FLOW_CUSTOM_SUCCESS, "custom-success", 0},
{GST_FLOW_OK, "ok", 0},
{GST_FLOW_NOT_LINKED, "not-linked", 0},
{GST_FLOW_FLUSHING, "flushing", 0},
{GST_FLOW_EOS, "eos", 0},
{GST_FLOW_NOT_NEGOTIATED, "not-negotiated", 0},
{GST_FLOW_ERROR, "error", 0},
{GST_FLOW_NOT_SUPPORTED, "not-supported", 0},
{GST_FLOW_CUSTOM_ERROR, "custom-error", 0}
};
/**
* gst_flow_get_name:
* @ret: a #GstFlowReturn to get the name of.
*
* Gets a string representing the given flow return.
*
* Returns: a static string with the name of the flow return.
*/
const gchar *
gst_flow_get_name (GstFlowReturn ret)
{
gint i;
ret = CLAMP (ret, GST_FLOW_CUSTOM_ERROR, GST_FLOW_CUSTOM_SUCCESS);
for (i = 0; i < G_N_ELEMENTS (flow_quarks); i++) {
if (ret == flow_quarks[i].ret)
return flow_quarks[i].name;
}
return "unknown";
}
/**
* gst_flow_to_quark:
* @ret: a #GstFlowReturn to get the quark of.
*
* Get the unique quark for the given GstFlowReturn.
*
* Returns: the quark associated with the flow return or 0 if an
* invalid return was specified.
*/
GQuark
gst_flow_to_quark (GstFlowReturn ret)
{
gint i;
ret = CLAMP (ret, GST_FLOW_CUSTOM_ERROR, GST_FLOW_CUSTOM_SUCCESS);
for (i = 0; i < G_N_ELEMENTS (flow_quarks); i++) {
if (ret == flow_quarks[i].ret)
return flow_quarks[i].quark;
}
return 0;
}
/**
* gst_pad_link_get_name:
* @ret: a #GstPadLinkReturn to get the name of.
*
* Gets a string representing the given pad-link return.
*
* Returns: a static string with the name of the pad-link return.
*
* Since: 1.4
*/
const gchar *
gst_pad_link_get_name (GstPadLinkReturn ret)
{
switch (ret) {
case GST_PAD_LINK_OK:
return "ok";
case GST_PAD_LINK_WRONG_HIERARCHY:
return "wrong hierarchy";
case GST_PAD_LINK_WAS_LINKED:
return "was linked";
case GST_PAD_LINK_WRONG_DIRECTION:
return "wrong direction";
case GST_PAD_LINK_NOFORMAT:
return "no common format";
case GST_PAD_LINK_NOSCHED:
return "incompatible scheduling";
case GST_PAD_LINK_REFUSED:
return "refused";
}
g_return_val_if_reached ("unknown");
}
#define _do_init \
{ \
gint i; \
\
buffer_quark = g_quark_from_static_string ("buffer"); \
buffer_list_quark = g_quark_from_static_string ("bufferlist"); \
event_quark = g_quark_from_static_string ("event"); \
\
for (i = 0; i < G_N_ELEMENTS (flow_quarks); i++) { \
flow_quarks[i].quark = g_quark_from_static_string (flow_quarks[i].name); \
} \
\
GST_DEBUG_CATEGORY_INIT (debug_dataflow, "GST_DATAFLOW", \
GST_DEBUG_BOLD | GST_DEBUG_FG_GREEN, "dataflow inside pads"); \
}
#define gst_pad_parent_class parent_class
G_DEFINE_TYPE_WITH_CODE (GstPad, gst_pad, GST_TYPE_OBJECT, _do_init);
static void
gst_pad_class_init (GstPadClass * klass)
{
GObjectClass *gobject_class;
GstObjectClass *gstobject_class;
gobject_class = G_OBJECT_CLASS (klass);
gstobject_class = GST_OBJECT_CLASS (klass);
g_type_class_add_private (klass, sizeof (GstPadPrivate));
gobject_class->dispose = gst_pad_dispose;
gobject_class->finalize = gst_pad_finalize;
gobject_class->set_property = gst_pad_set_property;
gobject_class->get_property = gst_pad_get_property;
/**
* GstPad::linked:
* @pad: the pad that emitted the signal
* @peer: the peer pad that has been connected
*
* Signals that a pad has been linked to the peer pad.
*/
gst_pad_signals[PAD_LINKED] =
g_signal_new ("linked", G_TYPE_FROM_CLASS (klass), G_SIGNAL_RUN_LAST,
G_STRUCT_OFFSET (GstPadClass, linked), NULL, NULL,
g_cclosure_marshal_generic, G_TYPE_NONE, 1, GST_TYPE_PAD);
/**
* GstPad::unlinked:
* @pad: the pad that emitted the signal
* @peer: the peer pad that has been disconnected
*
* Signals that a pad has been unlinked from the peer pad.
*/
gst_pad_signals[PAD_UNLINKED] =
g_signal_new ("unlinked", G_TYPE_FROM_CLASS (klass), G_SIGNAL_RUN_LAST,
G_STRUCT_OFFSET (GstPadClass, unlinked), NULL, NULL,
g_cclosure_marshal_generic, G_TYPE_NONE, 1, GST_TYPE_PAD);
pspec_caps = g_param_spec_boxed ("caps", "Caps",
"The capabilities of the pad", GST_TYPE_CAPS,
G_PARAM_READABLE | G_PARAM_STATIC_STRINGS);
g_object_class_install_property (gobject_class, PAD_PROP_CAPS, pspec_caps);
g_object_class_install_property (gobject_class, PAD_PROP_DIRECTION,
g_param_spec_enum ("direction", "Direction", "The direction of the pad",
GST_TYPE_PAD_DIRECTION, GST_PAD_UNKNOWN,
G_PARAM_READWRITE | G_PARAM_CONSTRUCT_ONLY | G_PARAM_STATIC_STRINGS));
/* FIXME, Make G_PARAM_CONSTRUCT_ONLY when we fix ghostpads. */
g_object_class_install_property (gobject_class, PAD_PROP_TEMPLATE,
g_param_spec_object ("template", "Template",
"The GstPadTemplate of this pad", GST_TYPE_PAD_TEMPLATE,
G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
/**
* GstPad:offset:
*
* The offset that will be applied to the running time of the pad.
*
* Since: 1.6
*/
g_object_class_install_property (gobject_class, PAD_PROP_OFFSET,
g_param_spec_int64 ("offset", "Offset",
"The running time offset of the pad", 0, G_MAXINT64, 0,
G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
gstobject_class->path_string_separator = ".";
/* Register common function pointer descriptions */
GST_DEBUG_REGISTER_FUNCPTR (gst_pad_activate_default);
GST_DEBUG_REGISTER_FUNCPTR (gst_pad_event_default);
GST_DEBUG_REGISTER_FUNCPTR (gst_pad_query_default);
GST_DEBUG_REGISTER_FUNCPTR (gst_pad_iterate_internal_links_default);
GST_DEBUG_REGISTER_FUNCPTR (gst_pad_chain_list_default);
}
static void
gst_pad_init (GstPad * pad)
{
pad->priv = GST_PAD_GET_PRIVATE (pad);
GST_PAD_DIRECTION (pad) = GST_PAD_UNKNOWN;
GST_PAD_ACTIVATEFUNC (pad) = gst_pad_activate_default;
GST_PAD_EVENTFUNC (pad) = gst_pad_event_default;
GST_PAD_QUERYFUNC (pad) = gst_pad_query_default;
GST_PAD_ITERINTLINKFUNC (pad) = gst_pad_iterate_internal_links_default;
GST_PAD_CHAINLISTFUNC (pad) = gst_pad_chain_list_default;
GST_PAD_SET_FLUSHING (pad);
g_rec_mutex_init (&pad->stream_rec_lock);
g_cond_init (&pad->block_cond);
g_hook_list_init (&pad->probes, sizeof (GstProbe));
pad->priv->events = g_array_sized_new (FALSE, TRUE, sizeof (PadEvent), 16);
pad->priv->events_cookie = 0;
pad->priv->last_cookie = -1;
pad->ABI.abi.last_flowret = GST_FLOW_FLUSHING;
}
/* called when setting the pad inactive. It removes all sticky events from
* the pad. must be called with object lock */
static void
remove_events (GstPad * pad)
{
guint i, len;
GArray *events;
gboolean notify = FALSE;
events = pad->priv->events;
len = events->len;
for (i = 0; i < len; i++) {
PadEvent *ev = &g_array_index (events, PadEvent, i);
GstEvent *event = ev->event;
ev->event = NULL;
if (event && GST_EVENT_TYPE (event) == GST_EVENT_CAPS)
notify = TRUE;
gst_event_unref (event);
}
GST_OBJECT_FLAG_UNSET (pad, GST_PAD_FLAG_PENDING_EVENTS);
g_array_set_size (events, 0);
pad->priv->events_cookie++;
if (notify) {
GST_OBJECT_UNLOCK (pad);
GST_DEBUG_OBJECT (pad, "notify caps");
g_object_notify_by_pspec ((GObject *) pad, pspec_caps);
GST_OBJECT_LOCK (pad);
}
}
/* should be called with object lock */
static PadEvent *
find_event_by_type (GstPad * pad, GstEventType type, guint idx)
{
guint i, len;
GArray *events;
PadEvent *ev;
events = pad->priv->events;
len = events->len;
for (i = 0; i < len; i++) {
ev = &g_array_index (events, PadEvent, i);
if (ev->event == NULL)
continue;
if (GST_EVENT_TYPE (ev->event) == type) {
if (idx == 0)
goto found;
idx--;
}
}
ev = NULL;
found:
return ev;
}
/* should be called with OBJECT lock */
static PadEvent *
find_event (GstPad * pad, GstEvent * event)
{
guint i, len;
GArray *events;
PadEvent *ev;
events = pad->priv->events;
len = events->len;
for (i = 0; i < len; i++) {
ev = &g_array_index (events, PadEvent, i);
if (event == ev->event)
goto found;
}
ev = NULL;
found:
return ev;
}
/* should be called with OBJECT lock */
static void
remove_event_by_type (GstPad * pad, GstEventType type)
{
guint i, len;
GArray *events;
PadEvent *ev;
events = pad->priv->events;
len = events->len;
i = 0;
while (i < len) {
ev = &g_array_index (events, PadEvent, i);
if (ev->event == NULL)
goto next;
if (GST_EVENT_TYPE (ev->event) != type)
goto next;
gst_event_unref (ev->event);
g_array_remove_index (events, i);
len--;
pad->priv->events_cookie++;
continue;
next:
i++;
}
}
/* check all events on srcpad against those on sinkpad. All events that are not
* on sinkpad are marked as received=%FALSE and the PENDING_EVENTS is set on the
* srcpad so that the events will be sent next time */
/* should be called with srcpad and sinkpad LOCKS */
static void
schedule_events (GstPad * srcpad, GstPad * sinkpad)
{
gint i, len;
GArray *events;
PadEvent *ev;
gboolean pending = FALSE;
events = srcpad->priv->events;
len = events->len;
for (i = 0; i < len; i++) {
ev = &g_array_index (events, PadEvent, i);
if (ev->event == NULL)
continue;
if (sinkpad == NULL || !find_event (sinkpad, ev->event)) {
ev->received = FALSE;
pending = TRUE;
}
}
if (pending)
GST_OBJECT_FLAG_SET (srcpad, GST_PAD_FLAG_PENDING_EVENTS);
}
typedef gboolean (*PadEventFunction) (GstPad * pad, PadEvent * ev,
gpointer user_data);
/* should be called with pad LOCK */
static void
events_foreach (GstPad * pad, PadEventFunction func, gpointer user_data)
{
guint i, len;
GArray *events;
gboolean ret;
guint cookie;
events = pad->priv->events;
restart:
cookie = pad->priv->events_cookie;
i = 0;
len = events->len;
while (i < len) {
PadEvent *ev, ev_ret;
ev = &g_array_index (events, PadEvent, i);
if (G_UNLIKELY (ev->event == NULL))
goto next;
/* take aditional ref, func might release the lock */
ev_ret.event = gst_event_ref (ev->event);
ev_ret.received = ev->received;
ret = func (pad, &ev_ret, user_data);
/* recheck the cookie, lock might have been released and the list could have
* changed */
if (G_UNLIKELY (cookie != pad->priv->events_cookie)) {
if (G_LIKELY (ev_ret.event))
gst_event_unref (ev_ret.event);
goto restart;
}
/* store the received state */
ev->received = ev_ret.received;
/* if the event changed, we need to do something */
if (G_UNLIKELY (ev->event != ev_ret.event)) {
if (G_UNLIKELY (ev_ret.event == NULL)) {
/* function unreffed and set the event to NULL, remove it */
gst_event_unref (ev->event);
g_array_remove_index (events, i);
len--;
cookie = ++pad->priv->events_cookie;
continue;
} else {
/* function gave a new event for us */
gst_event_take (&ev->event, ev_ret.event);
}
} else {
/* just unref, nothing changed */
gst_event_unref (ev_ret.event);
}
if (!ret)
break;
next:
i++;
}
}
/* should be called with LOCK */
static GstEvent *
_apply_pad_offset (GstPad * pad, GstEvent * event, gboolean upstream)
{
gint64 offset;
GST_DEBUG_OBJECT (pad, "apply pad offset %" GST_TIME_FORMAT,
GST_TIME_ARGS (pad->offset));
if (GST_EVENT_TYPE (event) == GST_EVENT_SEGMENT) {
GstSegment segment;
g_assert (!upstream);
/* copy segment values */
gst_event_copy_segment (event, &segment);
gst_event_unref (event);
gst_segment_offset_running_time (&segment, segment.format, pad->offset);
event = gst_event_new_segment (&segment);
}
event = gst_event_make_writable (event);
offset = gst_event_get_running_time_offset (event);
if (upstream)
offset -= pad->offset;
else
offset += pad->offset;
gst_event_set_running_time_offset (event, offset);
return event;
}
static inline GstEvent *
apply_pad_offset (GstPad * pad, GstEvent * event, gboolean upstream)
{
if (G_UNLIKELY (pad->offset != 0))
return _apply_pad_offset (pad, event, upstream);
return event;
}
/* should be called with the OBJECT_LOCK */
static GstCaps *
get_pad_caps (GstPad * pad)
{
GstCaps *caps = NULL;
PadEvent *ev;
ev = find_event_by_type (pad, GST_EVENT_CAPS, 0);
if (ev && ev->event)
gst_event_parse_caps (ev->event, &caps);
return caps;
}
static void
gst_pad_dispose (GObject * object)
{
GstPad *pad = GST_PAD_CAST (object);
GstPad *peer;
GST_CAT_DEBUG_OBJECT (GST_CAT_REFCOUNTING, pad, "dispose");
/* unlink the peer pad */
if ((peer = gst_pad_get_peer (pad))) {
/* window for MT unsafeness, someone else could unlink here
* and then we call unlink with wrong pads. The unlink
* function would catch this and safely return failed. */
if (GST_PAD_IS_SRC (pad))
gst_pad_unlink (pad, peer);
else
gst_pad_unlink (peer, pad);
gst_object_unref (peer);
}
gst_pad_set_pad_template (pad, NULL);
GST_OBJECT_LOCK (pad);
remove_events (pad);
GST_OBJECT_UNLOCK (pad);
g_hook_list_clear (&pad->probes);
G_OBJECT_CLASS (parent_class)->dispose (object);
}
static void
gst_pad_finalize (GObject * object)
{
GstPad *pad = GST_PAD_CAST (object);
GstTask *task;
/* in case the task is still around, clean it up */
if ((task = GST_PAD_TASK (pad))) {
gst_task_join (task);
GST_PAD_TASK (pad) = NULL;
gst_object_unref (task);
}
if (pad->activatenotify)
pad->activatenotify (pad->activatedata);
if (pad->activatemodenotify)
pad->activatemodenotify (pad->activatemodedata);
if (pad->linknotify)
pad->linknotify (pad->linkdata);
if (pad->unlinknotify)
pad->unlinknotify (pad->unlinkdata);
if (pad->chainnotify)
pad->chainnotify (pad->chaindata);
if (pad->chainlistnotify)
pad->chainlistnotify (pad->chainlistdata);
if (pad->getrangenotify)
pad->getrangenotify (pad->getrangedata);
if (pad->eventnotify)
pad->eventnotify (pad->eventdata);
if (pad->querynotify)
pad->querynotify (pad->querydata);
if (pad->iterintlinknotify)
pad->iterintlinknotify (pad->iterintlinkdata);
g_rec_mutex_clear (&pad->stream_rec_lock);
g_cond_clear (&pad->block_cond);
g_array_free (pad->priv->events, TRUE);
G_OBJECT_CLASS (parent_class)->finalize (object);
}
static void
gst_pad_set_property (GObject * object, guint prop_id,
const GValue * value, GParamSpec * pspec)
{
g_return_if_fail (GST_IS_PAD (object));
switch (prop_id) {
case PAD_PROP_DIRECTION:
GST_PAD_DIRECTION (object) = (GstPadDirection) g_value_get_enum (value);
break;
case PAD_PROP_TEMPLATE:
gst_pad_set_pad_template (GST_PAD_CAST (object),
(GstPadTemplate *) g_value_get_object (value));
break;
case PAD_PROP_OFFSET:
gst_pad_set_offset (GST_PAD_CAST (object), g_value_get_int64 (value));
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
break;
}
}
static void
gst_pad_get_property (GObject * object, guint prop_id,
GValue * value, GParamSpec * pspec)
{
g_return_if_fail (GST_IS_PAD (object));
switch (prop_id) {
case PAD_PROP_CAPS:
GST_OBJECT_LOCK (object);
g_value_set_boxed (value, get_pad_caps (GST_PAD_CAST (object)));
GST_OBJECT_UNLOCK (object);
break;
case PAD_PROP_DIRECTION:
g_value_set_enum (value, GST_PAD_DIRECTION (object));
break;
case PAD_PROP_TEMPLATE:
g_value_set_object (value, GST_PAD_PAD_TEMPLATE (object));
break;
case PAD_PROP_OFFSET:
g_value_set_int64 (value, gst_pad_get_offset (GST_PAD_CAST (object)));
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
break;
}
}
/**
* gst_pad_new:
* @name: (allow-none): the name of the new pad.
* @direction: the #GstPadDirection of the pad.
*
* Creates a new pad with the given name in the given direction.
* If name is %NULL, a guaranteed unique name (across all pads)
* will be assigned.
* This function makes a copy of the name so you can safely free the name.
*
* Returns: (transfer floating) (nullable): a new #GstPad, or %NULL in
* case of an error.
*
* MT safe.
*/
GstPad *
gst_pad_new (const gchar * name, GstPadDirection direction)
{
return g_object_new (GST_TYPE_PAD,
"name", name, "direction", direction, NULL);
}
/**
* gst_pad_new_from_template:
* @templ: the pad template to use
* @name: (allow-none): the name of the pad
*
* Creates a new pad with the given name from the given template.
* If name is %NULL, a guaranteed unique name (across all pads)
* will be assigned.
* This function makes a copy of the name so you can safely free the name.
*
* Returns: (transfer floating) (nullable): a new #GstPad, or %NULL in
* case of an error.
*/
GstPad *
gst_pad_new_from_template (GstPadTemplate * templ, const gchar * name)
{
g_return_val_if_fail (GST_IS_PAD_TEMPLATE (templ), NULL);
return g_object_new (GST_TYPE_PAD,
"name", name, "direction", templ->direction, "template", templ, NULL);
}
/**
* gst_pad_new_from_static_template:
* @templ: the #GstStaticPadTemplate to use
* @name: the name of the pad
*
* Creates a new pad with the given name from the given static template.
* If name is %NULL, a guaranteed unique name (across all pads)
* will be assigned.
* This function makes a copy of the name so you can safely free the name.
*
* Returns: (transfer floating) (nullable): a new #GstPad, or %NULL in
* case of an error.
*/
GstPad *
gst_pad_new_from_static_template (GstStaticPadTemplate * templ,
const gchar * name)
{
GstPad *pad;
GstPadTemplate *template;
template = gst_static_pad_template_get (templ);
pad = gst_pad_new_from_template (template, name);
gst_object_unref (template);
return pad;
}
#define ACQUIRE_PARENT(pad, parent, label) \
G_STMT_START { \
if (G_LIKELY ((parent = GST_OBJECT_PARENT (pad)))) \
gst_object_ref (parent); \
else if (G_LIKELY (GST_PAD_NEEDS_PARENT (pad))) \
goto label; \
} G_STMT_END
#define RELEASE_PARENT(parent) \
G_STMT_START { \
if (G_LIKELY (parent)) \
gst_object_unref (parent); \
} G_STMT_END
/**
* gst_pad_get_direction:
* @pad: a #GstPad to get the direction of.
*
* Gets the direction of the pad. The direction of the pad is
* decided at construction time so this function does not take
* the LOCK.
*
* Returns: the #GstPadDirection of the pad.
*
* MT safe.
*/
GstPadDirection
gst_pad_get_direction (GstPad * pad)
{
GstPadDirection result;
/* PAD_UNKNOWN is a little silly but we need some sort of
* error return value */
g_return_val_if_fail (GST_IS_PAD (pad), GST_PAD_UNKNOWN);
result = GST_PAD_DIRECTION (pad);
return result;
}
static gboolean
gst_pad_activate_default (GstPad * pad, GstObject * parent)
{
return gst_pad_activate_mode (pad, GST_PAD_MODE_PUSH, TRUE);
}
/**
* gst_pad_mode_get_name:
* @mode: the pad mode
*
* Return the name of a pad mode, for use in debug messages mostly.
*
* Returns: short mnemonic for pad mode @mode
*/
const gchar *
gst_pad_mode_get_name (GstPadMode mode)
{
switch (mode) {
case GST_PAD_MODE_NONE:
return "none";
case GST_PAD_MODE_PUSH:
return "push";
case GST_PAD_MODE_PULL:
return "pull";
default:
break;
}
return "unknown";
}
static void
pre_activate (GstPad * pad, GstPadMode new_mode)
{
switch (new_mode) {
case GST_PAD_MODE_NONE:
GST_OBJECT_LOCK (pad);
GST_DEBUG_OBJECT (pad, "setting PAD_MODE NONE, set flushing");
GST_PAD_SET_FLUSHING (pad);
pad->ABI.abi.last_flowret = GST_FLOW_FLUSHING;
GST_PAD_MODE (pad) = new_mode;
/* unlock blocked pads so element can resume and stop */
GST_PAD_BLOCK_BROADCAST (pad);
GST_OBJECT_UNLOCK (pad);
break;
case GST_PAD_MODE_PUSH:
case GST_PAD_MODE_PULL:
GST_OBJECT_LOCK (pad);
GST_DEBUG_OBJECT (pad, "setting pad into %s mode, unset flushing",
gst_pad_mode_get_name (new_mode));
GST_PAD_UNSET_FLUSHING (pad);
pad->ABI.abi.last_flowret = GST_FLOW_OK;
GST_PAD_MODE (pad) = new_mode;
if (GST_PAD_IS_SINK (pad)) {
GstPad *peer;
/* make sure the peer src pad sends us all events */
if ((peer = GST_PAD_PEER (pad))) {
gst_object_ref (peer);
GST_OBJECT_UNLOCK (pad);
GST_DEBUG_OBJECT (pad, "reschedule events on peer %s:%s",
GST_DEBUG_PAD_NAME (peer));
GST_OBJECT_LOCK (peer);
schedule_events (peer, NULL);
GST_OBJECT_UNLOCK (peer);
gst_object_unref (peer);
} else {
GST_OBJECT_UNLOCK (pad);
}
} else {
GST_OBJECT_UNLOCK (pad);
}
break;
}
}
static void
post_activate (GstPad * pad, GstPadMode new_mode)
{
switch (new_mode) {
case GST_PAD_MODE_NONE:
/* ensures that streaming stops */
GST_PAD_STREAM_LOCK (pad);
GST_DEBUG_OBJECT (pad, "stopped streaming");
GST_OBJECT_LOCK (pad);
remove_events (pad);
GST_OBJECT_UNLOCK (pad);
GST_PAD_STREAM_UNLOCK (pad);
break;
case GST_PAD_MODE_PUSH:
case GST_PAD_MODE_PULL:
/* NOP */
break;
}
}
/**
* gst_pad_set_active:
* @pad: the #GstPad to activate or deactivate.
* @active: whether or not the pad should be active.
*
* Activates or deactivates the given pad.
* Normally called from within core state change functions.
*
* If @active, makes sure the pad is active. If it is already active, either in
* push or pull mode, just return. Otherwise dispatches to the pad's activate
* function to perform the actual activation.
*
* If not @active, calls gst_pad_activate_mode() with the pad's current mode
* and a %FALSE argument.
*
* Returns: %TRUE if the operation was successful.
*
* MT safe.
*/
gboolean
gst_pad_set_active (GstPad * pad, gboolean active)
{
GstObject *parent;
GstPadMode old;
gboolean ret = FALSE;
g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
GST_OBJECT_LOCK (pad);
old = GST_PAD_MODE (pad);
ACQUIRE_PARENT (pad, parent, no_parent);
GST_OBJECT_UNLOCK (pad);
if (active) {
if (old == GST_PAD_MODE_NONE) {
GST_DEBUG_OBJECT (pad, "activating pad from none");
ret = (GST_PAD_ACTIVATEFUNC (pad)) (pad, parent);
if (ret)
pad->ABI.abi.last_flowret = GST_FLOW_OK;
} else {
GST_DEBUG_OBJECT (pad, "pad was active in %s mode",
gst_pad_mode_get_name (old));
ret = TRUE;
}
} else {
if (old == GST_PAD_MODE_NONE) {
GST_DEBUG_OBJECT (pad, "pad was inactive");
ret = TRUE;
} else {
GST_DEBUG_OBJECT (pad, "deactivating pad from %s mode",
gst_pad_mode_get_name (old));
ret = gst_pad_activate_mode (pad, old, FALSE);
if (ret)
pad->ABI.abi.last_flowret = GST_FLOW_FLUSHING;
}
}
RELEASE_PARENT (parent);
if (G_UNLIKELY (!ret))
goto failed;
return ret;
/* ERRORS */
no_parent:
{
GST_DEBUG_OBJECT (pad, "no parent");
GST_OBJECT_UNLOCK (pad);
return FALSE;
}
failed:
{
GST_OBJECT_LOCK (pad);
if (!active) {
g_critical ("Failed to deactivate pad %s:%s, very bad",
GST_DEBUG_PAD_NAME (pad));
} else {
GST_WARNING_OBJECT (pad, "Failed to activate pad");
}
GST_OBJECT_UNLOCK (pad);
return FALSE;
}
}
/**
* gst_pad_activate_mode:
* @pad: the #GstPad to activate or deactivate.
* @mode: the requested activation mode
* @active: whether or not the pad should be active.
*
* Activates or deactivates the given pad in @mode via dispatching to the
* pad's activatemodefunc. For use from within pad activation functions only.
*
* If you don't know what this is, you probably don't want to call it.
*
* Returns: %TRUE if the operation was successful.
*
* MT safe.
*/
gboolean
gst_pad_activate_mode (GstPad * pad, GstPadMode mode, gboolean active)
{
gboolean res = FALSE;
GstObject *parent;
GstPadMode old, new;
GstPadDirection dir;
GstPad *peer;
g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
GST_OBJECT_LOCK (pad);
old = GST_PAD_MODE (pad);
dir = GST_PAD_DIRECTION (pad);
ACQUIRE_PARENT (pad, parent, no_parent);
GST_OBJECT_UNLOCK (pad);
new = active ? mode : GST_PAD_MODE_NONE;
if (old == new)
goto was_ok;
if (active && old != mode && old != GST_PAD_MODE_NONE) {
/* pad was activate in the wrong direction, deactivate it
* and reactivate it in the requested mode */
GST_DEBUG_OBJECT (pad, "deactivating pad from %s mode",
gst_pad_mode_get_name (old));
if (G_UNLIKELY (!gst_pad_activate_mode (pad, old, FALSE)))
goto deactivate_failed;
}
switch (mode) {
case GST_PAD_MODE_PULL:
{
if (dir == GST_PAD_SINK) {
if ((peer = gst_pad_get_peer (pad))) {
GST_DEBUG_OBJECT (pad, "calling peer");
if (G_UNLIKELY (!gst_pad_activate_mode (peer, mode, active)))
goto peer_failed;
gst_object_unref (peer);
} else {
/* there is no peer, this is only fatal when we activate. When we
* deactivate, we must assume the application has unlinked the peer and
* will deactivate it eventually. */
if (active)
goto not_linked;
else
GST_DEBUG_OBJECT (pad, "deactivating unlinked pad");
}
} else {
if (G_UNLIKELY (GST_PAD_GETRANGEFUNC (pad) == NULL))
goto failure; /* Can't activate pull on a src without a
getrange function */
}
break;
}
default:
break;
}
/* Mark pad as needing reconfiguration */
if (active)
GST_OBJECT_FLAG_SET (pad, GST_PAD_FLAG_NEED_RECONFIGURE);
pre_activate (pad, new);
if (GST_PAD_ACTIVATEMODEFUNC (pad)) {
if (G_UNLIKELY (!GST_PAD_ACTIVATEMODEFUNC (pad) (pad, parent, mode,
active)))
goto failure;
} else {
/* can happen for sinks of passthrough elements */
}
post_activate (pad, new);
GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "%s in %s mode",
active ? "activated" : "deactivated", gst_pad_mode_get_name (mode));
exit_success:
res = TRUE;
/* Clear sticky flags on deactivation */
if (!active) {
GST_OBJECT_LOCK (pad);
GST_OBJECT_FLAG_UNSET (pad, GST_PAD_FLAG_NEED_RECONFIGURE);
GST_OBJECT_FLAG_UNSET (pad, GST_PAD_FLAG_EOS);
GST_OBJECT_UNLOCK (pad);
}
exit:
RELEASE_PARENT (parent);
return res;
no_parent:
{
GST_DEBUG_OBJECT (pad, "no parent");
GST_OBJECT_UNLOCK (pad);
return FALSE;
}
was_ok:
{
GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "already %s in %s mode",
active ? "activated" : "deactivated", gst_pad_mode_get_name (mode));
goto exit_success;
}
deactivate_failed:
{
GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad,
"failed to %s in switch to %s mode from %s mode",
(active ? "activate" : "deactivate"), gst_pad_mode_get_name (mode),
gst_pad_mode_get_name (old));
goto exit;
}
peer_failed:
{
GST_OBJECT_LOCK (peer);
GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad,
"activate_mode on peer (%s:%s) failed", GST_DEBUG_PAD_NAME (peer));
GST_OBJECT_UNLOCK (peer);
gst_object_unref (peer);
goto exit;
}
not_linked:
{
GST_CAT_INFO_OBJECT (GST_CAT_PADS, pad, "can't activate unlinked sink "
"pad in pull mode");
goto exit;
}
failure:
{
GST_OBJECT_LOCK (pad);
GST_CAT_INFO_OBJECT (GST_CAT_PADS, pad, "failed to %s in %s mode",
active ? "activate" : "deactivate", gst_pad_mode_get_name (mode));
GST_PAD_SET_FLUSHING (pad);
GST_PAD_MODE (pad) = old;
GST_OBJECT_UNLOCK (pad);
goto exit;
}
}
/**
* gst_pad_is_active:
* @pad: the #GstPad to query
*
* Query if a pad is active
*
* Returns: %TRUE if the pad is active.
*
* MT safe.
*/
gboolean
gst_pad_is_active (GstPad * pad)
{
gboolean result = FALSE;
g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
GST_OBJECT_LOCK (pad);
result = GST_PAD_IS_ACTIVE (pad);
GST_OBJECT_UNLOCK (pad);
return result;
}
static void
cleanup_hook (GstPad * pad, GHook * hook)
{
GstPadProbeType type;
if (!G_HOOK_IS_VALID (hook))
return;
type = (hook->flags) >> G_HOOK_FLAG_USER_SHIFT;
if (type & GST_PAD_PROBE_TYPE_BLOCKING) {
/* unblock when we remove the last blocking probe */
pad->num_blocked--;
GST_DEBUG_OBJECT (pad, "remove blocking probe, now %d left",
pad->num_blocked);
/* Might have new probes now that want to be called */
GST_PAD_BLOCK_BROADCAST (pad);
if (pad->num_blocked == 0) {
GST_DEBUG_OBJECT (pad, "last blocking probe removed, unblocking");
GST_OBJECT_FLAG_UNSET (pad, GST_PAD_FLAG_BLOCKED);
}
}
g_hook_destroy_link (&pad->probes, hook);
pad->num_probes--;
}
/**
* gst_pad_add_probe:
* @pad: the #GstPad to add the probe to
* @mask: the probe mask
* @callback: #GstPadProbeCallback that will be called with notifications of
* the pad state
* @user_data: (closure): user data passed to the callback
* @destroy_data: #GDestroyNotify for user_data
*
* Be notified of different states of pads. The provided callback is called for
* every state that matches @mask.
*
* Returns: an id or 0 if no probe is pending. The id can be used to remove the
* probe with gst_pad_remove_probe(). When using GST_PAD_PROBE_TYPE_IDLE it can
* happen that the probe can be run immediately and if the probe returns
* GST_PAD_PROBE_REMOVE this functions returns 0.
*
* MT safe.
*/
gulong
gst_pad_add_probe (GstPad * pad, GstPadProbeType mask,
GstPadProbeCallback callback, gpointer user_data,
GDestroyNotify destroy_data)
{
GHook *hook;
gulong res;
g_return_val_if_fail (GST_IS_PAD (pad), 0);
g_return_val_if_fail (mask != 0, 0);
GST_OBJECT_LOCK (pad);
/* make a new probe */
hook = g_hook_alloc (&pad->probes);
GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad, "adding probe for mask 0x%08x",
mask);
/* when no contraints are given for the types, assume all types are
* acceptable */
if ((mask & GST_PAD_PROBE_TYPE_ALL_BOTH) == 0)
mask |= GST_PAD_PROBE_TYPE_ALL_BOTH;
if ((mask & GST_PAD_PROBE_TYPE_SCHEDULING) == 0)
mask |= GST_PAD_PROBE_TYPE_SCHEDULING;
/* store our flags and other fields */
hook->flags |= (mask << G_HOOK_FLAG_USER_SHIFT);
hook->func = callback;
hook->data = user_data;
hook->destroy = destroy_data;
PROBE_COOKIE (hook) = (pad->priv->probe_cookie - 1);
/* add the probe */
g_hook_prepend (&pad->probes, hook);
pad->num_probes++;
/* incremenent cookie so that the new hook get's called */
pad->priv->probe_list_cookie++;
/* get the id of the hook, we return this and it can be used to remove the
* probe later */
res = hook->hook_id;
GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad, "got probe id %lu", res);
if (mask & GST_PAD_PROBE_TYPE_BLOCKING) {
/* we have a block probe */
pad->num_blocked++;
GST_OBJECT_FLAG_SET (pad, GST_PAD_FLAG_BLOCKED);
GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad, "added blocking probe, "
"now %d blocking probes", pad->num_blocked);
/* Might have new probes now that want to be called */
GST_PAD_BLOCK_BROADCAST (pad);
}
/* call the callback if we need to be called for idle callbacks */
if ((mask & GST_PAD_PROBE_TYPE_IDLE) && (callback != NULL)) {
if (pad->priv->using > 0) {
/* the pad is in use, we can't signal the idle callback yet. Since we set the
* flag above, the last thread to leave the push will do the callback. New
* threads going into the push will block. */
GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
"pad is in use, delay idle callback");
GST_OBJECT_UNLOCK (pad);
} else {
GstPadProbeInfo info = { GST_PAD_PROBE_TYPE_IDLE, res, };
GstPadProbeReturn ret;
/* Keep another ref, the callback could destroy the pad */
gst_object_ref (pad);
pad->priv->idle_running++;
/* the pad is idle now, we can signal the idle callback now */
GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad,
"pad is idle, trigger idle callback");
GST_OBJECT_UNLOCK (pad);
ret = callback (pad, &info, user_data);
GST_OBJECT_LOCK (pad);
switch (ret) {
case GST_PAD_PROBE_REMOVE:
/* remove the probe */
GST_DEBUG_OBJECT (pad, "asked to remove hook");
cleanup_hook (pad, hook);
res = 0;
break;
case GST_PAD_PROBE_DROP:
GST_DEBUG_OBJECT (pad, "asked to drop item");
break;
case GST_PAD_PROBE_PASS:
GST_DEBUG_OBJECT (pad, "asked to pass item");
break;
case GST_PAD_PROBE_OK:
GST_DEBUG_OBJECT (pad, "probe returned OK");
break;
default:
GST_DEBUG_OBJECT (pad, "probe returned %d", ret);
break;
}
pad->priv->idle_running--;
if (pad->priv->idle_running == 0) {
GST_PAD_BLOCK_BROADCAST (pad);
}
GST_OBJECT_UNLOCK (pad);
gst_object_unref (pad);
}
} else {
GST_OBJECT_UNLOCK (pad);
}
return res;
}
/**
* gst_pad_remove_probe:
* @pad: the #GstPad with the probe
* @id: the probe id to remove
*
* Remove the probe with @id from @pad.
*
* MT safe.
*/
void
gst_pad_remove_probe (GstPad * pad, gulong id)
{
GHook *hook;
g_return_if_fail (GST_IS_PAD (pad));
GST_OBJECT_LOCK (pad);
hook = g_hook_get (&pad->probes, id);
if (hook == NULL)
goto not_found;
GST_CAT_LOG_OBJECT (GST_CAT_SCHEDULING, pad, "removing hook %ld",
hook->hook_id);
cleanup_hook (pad, hook);
GST_OBJECT_UNLOCK (pad);
return;
not_found:
{
GST_OBJECT_UNLOCK (pad);
g_warning ("%s: pad `%p' has no probe with id `%lu'", G_STRLOC, pad, id);
return;
}
}
/**
* gst_pad_is_blocked:
* @pad: the #GstPad to query
*
* Checks if the pad is blocked or not. This function returns the
* last requested state of the pad. It is not certain that the pad
* is actually blocking at this point (see gst_pad_is_blocking()).
*
* Returns: %TRUE if the pad is blocked.
*
* MT safe.
*/
gboolean
gst_pad_is_blocked (GstPad * pad)
{
gboolean result = FALSE;
g_return_val_if_fail (GST_IS_PAD (pad), result);
GST_OBJECT_LOCK (pad);
result = GST_OBJECT_FLAG_IS_SET (pad, GST_PAD_FLAG_BLOCKED);
GST_OBJECT_UNLOCK (pad);
return result;
}
/**
* gst_pad_is_blocking:
* @pad: the #GstPad to query
*
* Checks if the pad is blocking or not. This is a guaranteed state
* of whether the pad is actually blocking on a #GstBuffer or a #GstEvent.
*
* Returns: %TRUE if the pad is blocking.
*
* MT safe.
*/
gboolean
gst_pad_is_blocking (GstPad * pad)
{
gboolean result = FALSE;
g_return_val_if_fail (GST_IS_PAD (pad), result);
GST_OBJECT_LOCK (pad);
/* the blocking flag is only valid if the pad is not flushing */
result = GST_PAD_IS_BLOCKING (pad) && !GST_PAD_IS_FLUSHING (pad);
GST_OBJECT_UNLOCK (pad);
return result;
}
/**
* gst_pad_needs_reconfigure:
* @pad: the #GstPad to check
*
* Check the #GST_PAD_FLAG_NEED_RECONFIGURE flag on @pad and return %TRUE
* if the flag was set.
*
* Returns: %TRUE is the GST_PAD_FLAG_NEED_RECONFIGURE flag is set on @pad.
*/
gboolean
gst_pad_needs_reconfigure (GstPad * pad)
{
gboolean reconfigure;
g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
GST_OBJECT_LOCK (pad);
reconfigure = GST_PAD_NEEDS_RECONFIGURE (pad);
GST_DEBUG_OBJECT (pad, "peeking RECONFIGURE flag %d", reconfigure);
GST_OBJECT_UNLOCK (pad);
return reconfigure;
}
/**
* gst_pad_check_reconfigure:
* @pad: the #GstPad to check
*
* Check and clear the #GST_PAD_FLAG_NEED_RECONFIGURE flag on @pad and return %TRUE
* if the flag was set.
*
* Returns: %TRUE is the GST_PAD_FLAG_NEED_RECONFIGURE flag was set on @pad.
*/
gboolean
gst_pad_check_reconfigure (GstPad * pad)
{
gboolean reconfigure;
g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
GST_OBJECT_LOCK (pad);
reconfigure = GST_PAD_NEEDS_RECONFIGURE (pad);
if (reconfigure) {
GST_DEBUG_OBJECT (pad, "remove RECONFIGURE flag");
GST_OBJECT_FLAG_UNSET (pad, GST_PAD_FLAG_NEED_RECONFIGURE);
}
GST_OBJECT_UNLOCK (pad);
return reconfigure;
}
/**
* gst_pad_mark_reconfigure:
* @pad: the #GstPad to mark
*
* Mark a pad for needing reconfiguration. The next call to
* gst_pad_check_reconfigure() will return %TRUE after this call.
*/
void
gst_pad_mark_reconfigure (GstPad * pad)
{
g_return_if_fail (GST_IS_PAD (pad));
GST_OBJECT_LOCK (pad);
GST_OBJECT_FLAG_SET (pad, GST_PAD_FLAG_NEED_RECONFIGURE);
GST_OBJECT_UNLOCK (pad);
}
/**
* gst_pad_set_activate_function:
* @p: a #GstPad.
* @f: the #GstPadActivateFunction to set.
*
* Calls gst_pad_set_activate_function_full() with %NULL for the user_data and
* notify.
*/
/**
* gst_pad_set_activate_function_full:
* @pad: a #GstPad.
* @activate: the #GstPadActivateFunction to set.
* @user_data: user_data passed to @notify
* @notify: notify called when @activate will not be used anymore.
*
* Sets the given activate function for @pad. The activate function will
* dispatch to gst_pad_activate_mode() to perform the actual activation.
* Only makes sense to set on sink pads.
*
* Call this function if your sink pad can start a pull-based task.
*/
void
gst_pad_set_activate_function_full (GstPad * pad,
GstPadActivateFunction activate, gpointer user_data, GDestroyNotify notify)
{
g_return_if_fail (GST_IS_PAD (pad));
if (pad->activatenotify)
pad->activatenotify (pad->activatedata);
GST_PAD_ACTIVATEFUNC (pad) = activate;
pad->activatedata = user_data;
pad->activatenotify = notify;
GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "activatefunc set to %s",
GST_DEBUG_FUNCPTR_NAME (activate));
}
/**
* gst_pad_set_activatemode_function:
* @p: a #GstPad.
* @f: the #GstPadActivateModeFunction to set.
*
* Calls gst_pad_set_activatemode_function_full() with %NULL for the user_data and
* notify.
*/
/**
* gst_pad_set_activatemode_function_full:
* @pad: a #GstPad.
* @activatemode: the #GstPadActivateModeFunction to set.
* @user_data: user_data passed to @notify
* @notify: notify called when @activatemode will not be used anymore.
*
* Sets the given activate_mode function for the pad. An activate_mode function
* prepares the element for data passing.
*/
void
gst_pad_set_activatemode_function_full (GstPad * pad,
GstPadActivateModeFunction activatemode, gpointer user_data,
GDestroyNotify notify)
{
g_return_if_fail (GST_IS_PAD (pad));
if (pad->activatemodenotify)
pad->activatemodenotify (pad->activatemodedata);
GST_PAD_ACTIVATEMODEFUNC (pad) = activatemode;
pad->activatemodedata = user_data;
pad->activatemodenotify = notify;
GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "activatemodefunc set to %s",
GST_DEBUG_FUNCPTR_NAME (activatemode));
}
/**
* gst_pad_set_chain_function:
* @p: a sink #GstPad.
* @f: the #GstPadChainFunction to set.
*
* Calls gst_pad_set_chain_function_full() with %NULL for the user_data and
* notify.
*/
/**
* gst_pad_set_chain_function_full:
* @pad: a sink #GstPad.
* @chain: the #GstPadChainFunction to set.
* @user_data: user_data passed to @notify
* @notify: notify called when @chain will not be used anymore.
*
* Sets the given chain function for the pad. The chain function is called to
* process a #GstBuffer input buffer. see #GstPadChainFunction for more details.
*/
void
gst_pad_set_chain_function_full (GstPad * pad, GstPadChainFunction chain,
gpointer user_data, GDestroyNotify notify)
{
g_return_if_fail (GST_IS_PAD (pad));
g_return_if_fail (GST_PAD_IS_SINK (pad));
if (pad->chainnotify)
pad->chainnotify (pad->chaindata);
GST_PAD_CHAINFUNC (pad) = chain;
pad->chaindata = user_data;
pad->chainnotify = notify;
GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "chainfunc set to %s",
GST_DEBUG_FUNCPTR_NAME (chain));
}
/**
* gst_pad_set_chain_list_function:
* @p: a sink #GstPad.
* @f: the #GstPadChainListFunction to set.
*
* Calls gst_pad_set_chain_list_function_full() with %NULL for the user_data and
* notify.
*/
/**
* gst_pad_set_chain_list_function_full:
* @pad: a sink #GstPad.
* @chainlist: the #GstPadChainListFunction to set.
* @user_data: user_data passed to @notify
* @notify: notify called when @chainlist will not be used anymore.
*
* Sets the given chain list function for the pad. The chainlist function is
* called to process a #GstBufferList input buffer list. See
* #GstPadChainListFunction for more details.
*/
void
gst_pad_set_chain_list_function_full (GstPad * pad,
GstPadChainListFunction chainlist, gpointer user_data,
GDestroyNotify notify)
{
g_return_if_fail (GST_IS_PAD (pad));
g_return_if_fail (GST_PAD_IS_SINK (pad));
if (pad->chainlistnotify)
pad->chainlistnotify (pad->chainlistdata);
GST_PAD_CHAINLISTFUNC (pad) = chainlist;
pad->chainlistdata = user_data;
pad->chainlistnotify = notify;
GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "chainlistfunc set to %s",
GST_DEBUG_FUNCPTR_NAME (chainlist));
}
/**
* gst_pad_set_getrange_function:
* @p: a source #GstPad.
* @f: the #GstPadGetRangeFunction to set.
*
* Calls gst_pad_set_getrange_function_full() with %NULL for the user_data and
* notify.
*/
/**
* gst_pad_set_getrange_function_full:
* @pad: a source #GstPad.
* @get: the #GstPadGetRangeFunction to set.
* @user_data: user_data passed to @notify
* @notify: notify called when @get will not be used anymore.
*
* Sets the given getrange function for the pad. The getrange function is
* called to produce a new #GstBuffer to start the processing pipeline. see
* #GstPadGetRangeFunction for a description of the getrange function.
*/
void
gst_pad_set_getrange_function_full (GstPad * pad, GstPadGetRangeFunction get,
gpointer user_data, GDestroyNotify notify)
{
g_return_if_fail (GST_IS_PAD (pad));
g_return_if_fail (GST_PAD_IS_SRC (pad));
if (pad->getrangenotify)
pad->getrangenotify (pad->getrangedata);
GST_PAD_GETRANGEFUNC (pad) = get;
pad->getrangedata = user_data;
pad->getrangenotify = notify;
GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "getrangefunc set to %s",
GST_DEBUG_FUNCPTR_NAME (get));
}
/**
* gst_pad_set_event_function:
* @p: a #GstPad of either direction.
* @f: the #GstPadEventFunction to set.
*
* Calls gst_pad_set_event_function_full() with %NULL for the user_data and
* notify.
*/
/**
* gst_pad_set_event_function_full:
* @pad: a #GstPad of either direction.
* @event: the #GstPadEventFunction to set.
* @user_data: user_data passed to @notify
* @notify: notify called when @event will not be used anymore.
*
* Sets the given event handler for the pad.
*/
void
gst_pad_set_event_function_full (GstPad * pad, GstPadEventFunction event,
gpointer user_data, GDestroyNotify notify)
{
g_return_if_fail (GST_IS_PAD (pad));
if (pad->eventnotify)
pad->eventnotify (pad->eventdata);
GST_PAD_EVENTFUNC (pad) = event;
pad->eventdata = user_data;
pad->eventnotify = notify;
GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "eventfunc for set to %s",
GST_DEBUG_FUNCPTR_NAME (event));
}
/**
* gst_pad_set_query_function:
* @p: a #GstPad of either direction.
* @f: the #GstPadQueryFunction to set.
*
* Calls gst_pad_set_query_function_full() with %NULL for the user_data and
* notify.
*/
/**
* gst_pad_set_query_function_full:
* @pad: a #GstPad of either direction.
* @query: the #GstPadQueryFunction to set.
* @user_data: user_data passed to @notify
* @notify: notify called when @query will not be used anymore.
*
* Set the given query function for the pad.
*/
void
gst_pad_set_query_function_full (GstPad * pad, GstPadQueryFunction query,
gpointer user_data, GDestroyNotify notify)
{
g_return_if_fail (GST_IS_PAD (pad));
if (pad->querynotify)
pad->querynotify (pad->querydata);
GST_PAD_QUERYFUNC (pad) = query;
pad->querydata = user_data;
pad->querynotify = notify;
GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "queryfunc set to %s",
GST_DEBUG_FUNCPTR_NAME (query));
}
/**
* gst_pad_set_iterate_internal_links_function:
* @p: a #GstPad of either direction.
* @f: the #GstPadIterIntLinkFunction to set.
*
* Calls gst_pad_set_iterate_internal_links_function_full() with %NULL
* for the user_data and notify.
*/
/**
* gst_pad_set_iterate_internal_links_function_full:
* @pad: a #GstPad of either direction.
* @iterintlink: the #GstPadIterIntLinkFunction to set.
* @user_data: user_data passed to @notify
* @notify: notify called when @iterintlink will not be used anymore.
*
* Sets the given internal link iterator function for the pad.
*/
void
gst_pad_set_iterate_internal_links_function_full (GstPad * pad,
GstPadIterIntLinkFunction iterintlink, gpointer user_data,
GDestroyNotify notify)
{
g_return_if_fail (GST_IS_PAD (pad));
if (pad->iterintlinknotify)
pad->iterintlinknotify (pad->iterintlinkdata);
GST_PAD_ITERINTLINKFUNC (pad) = iterintlink;
pad->iterintlinkdata = user_data;
pad->iterintlinknotify = notify;
GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "internal link iterator set to %s",
GST_DEBUG_FUNCPTR_NAME (iterintlink));
}
/**
* gst_pad_set_link_function:
* @p: a #GstPad.
* @f: the #GstPadLinkFunction to set.
*
* Calls gst_pad_set_link_function_full() with %NULL
* for the user_data and notify.
*/
/**
* gst_pad_set_link_function_full:
* @pad: a #GstPad.
* @link: the #GstPadLinkFunction to set.
* @user_data: user_data passed to @notify
* @notify: notify called when @link will not be used anymore.
*
* Sets the given link function for the pad. It will be called when
* the pad is linked with another pad.
*
* The return value #GST_PAD_LINK_OK should be used when the connection can be
* made.
*
* The return value #GST_PAD_LINK_REFUSED should be used when the connection
* cannot be made for some reason.
*
* If @link is installed on a source pad, it should call the #GstPadLinkFunction
* of the peer sink pad, if present.
*/
void
gst_pad_set_link_function_full (GstPad * pad, GstPadLinkFunction link,
gpointer user_data, GDestroyNotify notify)
{
g_return_if_fail (GST_IS_PAD (pad));
if (pad->linknotify)
pad->linknotify (pad->linkdata);
GST_PAD_LINKFUNC (pad) = link;
pad->linkdata = user_data;
pad->linknotify = notify;
GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "linkfunc set to %s",
GST_DEBUG_FUNCPTR_NAME (link));
}
/**
* gst_pad_set_unlink_function:
* @p: a #GstPad.
* @f: the #GstPadUnlinkFunction to set.
*
* Calls gst_pad_set_unlink_function_full() with %NULL
* for the user_data and notify.
*/
/**
* gst_pad_set_unlink_function_full:
* @pad: a #GstPad.
* @unlink: the #GstPadUnlinkFunction to set.
* @user_data: user_data passed to @notify
* @notify: notify called when @unlink will not be used anymore.
*
* Sets the given unlink function for the pad. It will be called
* when the pad is unlinked.
*/
void
gst_pad_set_unlink_function_full (GstPad * pad, GstPadUnlinkFunction unlink,
gpointer user_data, GDestroyNotify notify)
{
g_return_if_fail (GST_IS_PAD (pad));
if (pad->unlinknotify)
pad->unlinknotify (pad->unlinkdata);
GST_PAD_UNLINKFUNC (pad) = unlink;
pad->unlinkdata = user_data;
pad->unlinknotify = notify;
GST_CAT_DEBUG_OBJECT (GST_CAT_PADS, pad, "unlinkfunc set to %s",
GST_DEBUG_FUNCPTR_NAME (unlink));
}
/**
* gst_pad_unlink:
* @srcpad: the source #GstPad to unlink.
* @sinkpad: the sink #GstPad to unlink.
*
* Unlinks the source pad from the sink pad. Will emit the #GstPad::unlinked
* signal on both pads.
*
* Returns: %TRUE if the pads were unlinked. This function returns %FALSE if
* the pads were not linked together.
*
* MT safe.
*/
gboolean
gst_pad_unlink (GstPad * srcpad, GstPad * sinkpad)
{
gboolean result = FALSE;
GstElement *parent = NULL;
g_return_val_if_fail (GST_IS_PAD (srcpad), FALSE);
g_return_val_if_fail (GST_PAD_IS_SRC (srcpad), FALSE);
g_return_val_if_fail (GST_IS_PAD (sinkpad), FALSE);
g_return_val_if_fail (GST_PAD_IS_SINK (sinkpad), FALSE);
GST_CAT_INFO (GST_CAT_ELEMENT_PADS, "unlinking %s:%s(%p) and %s:%s(%p)",
GST_DEBUG_PAD_NAME (srcpad), srcpad,
GST_DEBUG_PAD_NAME (sinkpad), sinkpad);
/* We need to notify the parent before taking any pad locks as the bin in
* question might be waiting for a lock on the pad while holding its lock
* that our message will try to take. */
if ((parent = GST_ELEMENT_CAST (gst_pad_get_parent (srcpad)))) {
if (GST_IS_ELEMENT (parent)) {
gst_element_post_message (parent,
gst_message_new_structure_change (GST_OBJECT_CAST (sinkpad),
GST_STRUCTURE_CHANGE_TYPE_PAD_UNLINK, parent, TRUE));
} else {
gst_object_unref (parent);
parent = NULL;
}
}
GST_OBJECT_LOCK (srcpad);
GST_OBJECT_LOCK (sinkpad);
if (G_UNLIKELY (GST_PAD_PEER (srcpad) != sinkpad))
goto not_linked_together;
if (GST_PAD_UNLINKFUNC (srcpad)) {
GstObject *tmpparent;
ACQUIRE_PARENT (srcpad, tmpparent, no_src_parent);
GST_PAD_UNLINKFUNC (srcpad) (srcpad, tmpparent);
RELEASE_PARENT (tmpparent);
}
no_src_parent:
if (GST_PAD_UNLINKFUNC (sinkpad)) {
GstObject *tmpparent;
ACQUIRE_PARENT (sinkpad, tmpparent, no_sink_parent);
GST_PAD_UNLINKFUNC (sinkpad) (sinkpad, tmpparent);
RELEASE_PARENT (tmpparent);
}
no_sink_parent:
/* first clear peers */
GST_PAD_PEER (srcpad) = NULL;
GST_PAD_PEER (sinkpad) = NULL;
GST_OBJECT_UNLOCK (sinkpad);
GST_OBJECT_UNLOCK (srcpad);
/* fire off a signal to each of the pads telling them
* that they've been unlinked */
g_signal_emit (srcpad, gst_pad_signals[PAD_UNLINKED], 0, sinkpad);
g_signal_emit (sinkpad, gst_pad_signals[PAD_UNLINKED], 0, srcpad);
GST_CAT_INFO (GST_CAT_ELEMENT_PADS, "unlinked %s:%s and %s:%s",
GST_DEBUG_PAD_NAME (srcpad), GST_DEBUG_PAD_NAME (sinkpad));
result = TRUE;
done:
if (parent != NULL) {
gst_element_post_message (parent,
gst_message_new_structure_change (GST_OBJECT_CAST (sinkpad),
GST_STRUCTURE_CHANGE_TYPE_PAD_UNLINK, parent, FALSE));
gst_object_unref (parent);
}
return result;
/* ERRORS */
not_linked_together:
{
/* we do not emit a warning in this case because unlinking cannot
* be made MT safe.*/
GST_OBJECT_UNLOCK (sinkpad);
GST_OBJECT_UNLOCK (srcpad);
goto done;
}
}
/**
* gst_pad_is_linked:
* @pad: pad to check
*
* Checks if a @pad is linked to another pad or not.
*
* Returns: %TRUE if the pad is linked, %FALSE otherwise.
*
* MT safe.
*/
gboolean
gst_pad_is_linked (GstPad * pad)
{
gboolean result;
g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
GST_OBJECT_LOCK (pad);
result = (GST_PAD_PEER (pad) != NULL);
GST_OBJECT_UNLOCK (pad);
return result;
}
/* get the caps from both pads and see if the intersection
* is not empty.
*
* This function should be called with the pad LOCK on both
* pads
*/
static gboolean
gst_pad_link_check_compatible_unlocked (GstPad * src, GstPad * sink,
GstPadLinkCheck flags)
{
GstCaps *srccaps = NULL;
GstCaps *sinkcaps = NULL;
gboolean compatible = FALSE;
if (!(flags & (GST_PAD_LINK_CHECK_CAPS | GST_PAD_LINK_CHECK_TEMPLATE_CAPS)))
return TRUE;
/* Doing the expensive caps checking takes priority over only checking the template caps */
if (flags & GST_PAD_LINK_CHECK_CAPS) {
GST_OBJECT_UNLOCK (sink);
GST_OBJECT_UNLOCK (src);
srccaps = gst_pad_query_caps (src, NULL);
sinkcaps = gst_pad_query_caps (sink, NULL);
GST_OBJECT_LOCK (src);
GST_OBJECT_LOCK (sink);
} else {
/* If one of the two pads doesn't have a template, consider the intersection
* as valid.*/
if (G_UNLIKELY ((GST_PAD_PAD_TEMPLATE (src) == NULL)
|| (GST_PAD_PAD_TEMPLATE (sink) == NULL))) {
compatible = TRUE;
goto done;
}
srccaps = gst_caps_ref (GST_PAD_TEMPLATE_CAPS (GST_PAD_PAD_TEMPLATE (src)));
sinkcaps =
gst_caps_ref (GST_PAD_TEMPLATE_CAPS (GST_PAD_PAD_TEMPLATE (sink)));
}
GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, src, "src caps %" GST_PTR_FORMAT,
srccaps);
GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, sink, "sink caps %" GST_PTR_FORMAT,
sinkcaps);
/* if we have caps on both pads we can check the intersection. If one
* of the caps is %NULL, we return %TRUE. */
if (G_UNLIKELY (srccaps == NULL || sinkcaps == NULL)) {
if (srccaps)
gst_caps_unref (srccaps);
if (sinkcaps)
gst_caps_unref (sinkcaps);
goto done;
}
compatible = gst_caps_can_intersect (srccaps, sinkcaps);
gst_caps_unref (srccaps);
gst_caps_unref (sinkcaps);
done:
GST_CAT_DEBUG (GST_CAT_CAPS, "caps are %scompatible",
(compatible ? "" : "not "));
return compatible;
}
/* check if the grandparents of both pads are the same.
* This check is required so that we don't try to link
* pads from elements in different bins without ghostpads.
*
* The LOCK should be held on both pads
*/
static gboolean
gst_pad_link_check_hierarchy (GstPad * src, GstPad * sink)
{
GstObject *psrc, *psink;
psrc = GST_OBJECT_PARENT (src);
psink = GST_OBJECT_PARENT (sink);
/* if one of the pads has no parent, we allow the link */
if (G_UNLIKELY (psrc == NULL || psink == NULL))
goto no_parent;
/* only care about parents that are elements */
if (G_UNLIKELY (!GST_IS_ELEMENT (psrc) || !GST_IS_ELEMENT (psink)))
goto no_element_parent;
/* if the parents are the same, we have a loop */
if (G_UNLIKELY (psrc == psink))
goto same_parents;
/* if they both have a parent, we check the grandparents. We can not lock
* the parent because we hold on the child (pad) and the locking order is
* parent >> child. */
psrc = GST_OBJECT_PARENT (psrc);
psink = GST_OBJECT_PARENT (psink);
/* if they have grandparents but they are not the same */
if (G_UNLIKELY (psrc != psink))
goto wrong_grandparents;
return TRUE;
/* ERRORS */
no_parent:
{
GST_CAT_DEBUG (GST_CAT_CAPS,
"one of the pads has no parent %" GST_PTR_FORMAT " and %"
GST_PTR_FORMAT, psrc, psink);
return TRUE;
}
no_element_parent:
{
GST_CAT_DEBUG (GST_CAT_CAPS,
"one of the pads has no element parent %" GST_PTR_FORMAT " and %"
GST_PTR_FORMAT, psrc, psink);
return TRUE;
}
same_parents:
{
GST_CAT_DEBUG (GST_CAT_CAPS, "pads have same parent %" GST_PTR_FORMAT,
psrc);
return FALSE;
}
wrong_grandparents:
{
GST_CAT_DEBUG (GST_CAT_CAPS,
"pads have different grandparents %" GST_PTR_FORMAT " and %"
GST_PTR_FORMAT, psrc, psink);
return FALSE;
}
}
/* FIXME leftover from an attempt at refactoring... */
/* call with the two pads unlocked, when this function returns GST_PAD_LINK_OK,
* the two pads will be locked in the srcpad, sinkpad order. */
static GstPadLinkReturn
gst_pad_link_prepare (GstPad * srcpad, GstPad * sinkpad, GstPadLinkCheck flags)
{
GST_CAT_INFO (GST_CAT_PADS, "trying to link %s:%s and %s:%s",
GST_DEBUG_PAD_NAME (srcpad), GST_DEBUG_PAD_NAME (sinkpad));
GST_OBJECT_LOCK (srcpad);
if (G_UNLIKELY (GST_PAD_PEER (srcpad) != NULL))
goto src_was_linked;
GST_OBJECT_LOCK (sinkpad);
if (G_UNLIKELY (GST_PAD_PEER (sinkpad) != NULL))
goto sink_was_linked;
/* check hierarchy, pads can only be linked if the grandparents
* are the same. */
if ((flags & GST_PAD_LINK_CHECK_HIERARCHY)
&& !gst_pad_link_check_hierarchy (srcpad, sinkpad))
goto wrong_hierarchy;
/* check pad caps for non-empty intersection */
if (!gst_pad_link_check_compatible_unlocked (srcpad, sinkpad, flags))
goto no_format;
/* FIXME check pad scheduling for non-empty intersection */
return GST_PAD_LINK_OK;
src_was_linked:
{
GST_CAT_INFO (GST_CAT_PADS, "src %s:%s was already linked to %s:%s",
GST_DEBUG_PAD_NAME (srcpad),
GST_DEBUG_PAD_NAME (GST_PAD_PEER (srcpad)));
/* we do not emit a warning in this case because unlinking cannot
* be made MT safe.*/
GST_OBJECT_UNLOCK (srcpad);
return GST_PAD_LINK_WAS_LINKED;
}
sink_was_linked:
{
GST_CAT_INFO (GST_CAT_PADS, "sink %s:%s was already linked to %s:%s",
GST_DEBUG_PAD_NAME (sinkpad),
GST_DEBUG_PAD_NAME (GST_PAD_PEER (sinkpad)));
/* we do not emit a warning in this case because unlinking cannot
* be made MT safe.*/
GST_OBJECT_UNLOCK (sinkpad);
GST_OBJECT_UNLOCK (srcpad);
return GST_PAD_LINK_WAS_LINKED;
}
wrong_hierarchy:
{
GST_CAT_INFO (GST_CAT_PADS, "pads have wrong hierarchy");
GST_OBJECT_UNLOCK (sinkpad);
GST_OBJECT_UNLOCK (srcpad);
return GST_PAD_LINK_WRONG_HIERARCHY;
}
no_format:
{
GST_CAT_INFO (GST_CAT_PADS, "caps are incompatible");
GST_OBJECT_UNLOCK (sinkpad);
GST_OBJECT_UNLOCK (srcpad);
return GST_PAD_LINK_NOFORMAT;
}
}
/**
* gst_pad_can_link:
* @srcpad: the source #GstPad.
* @sinkpad: the sink #GstPad.
*
* Checks if the source pad and the sink pad are compatible so they can be
* linked.
*
* Returns: %TRUE if the pads can be linked.
*/
gboolean
gst_pad_can_link (GstPad * srcpad, GstPad * sinkpad)
{
GstPadLinkReturn result;
/* generic checks */
g_return_val_if_fail (GST_IS_PAD (srcpad), FALSE);
g_return_val_if_fail (GST_IS_PAD (sinkpad), FALSE);
GST_CAT_INFO (GST_CAT_PADS, "check if %s:%s can link with %s:%s",
GST_DEBUG_PAD_NAME (srcpad), GST_DEBUG_PAD_NAME (sinkpad));
/* gst_pad_link_prepare does everything for us, we only release the locks
* on the pads that it gets us. If this function returns !OK the locks are not
* taken anymore. */
result = gst_pad_link_prepare (srcpad, sinkpad, GST_PAD_LINK_CHECK_DEFAULT);
if (result != GST_PAD_LINK_OK)
goto done;
GST_OBJECT_UNLOCK (srcpad);
GST_OBJECT_UNLOCK (sinkpad);
done:
return result == GST_PAD_LINK_OK;
}
/**
* gst_pad_link_full:
* @srcpad: the source #GstPad to link.
* @sinkpad: the sink #GstPad to link.
* @flags: the checks to validate when linking
*
* Links the source pad and the sink pad.
*
* This variant of #gst_pad_link provides a more granular control on the
* checks being done when linking. While providing some considerable speedups
* the caller of this method must be aware that wrong usage of those flags
* can cause severe issues. Refer to the documentation of #GstPadLinkCheck
* for more information.
*
* MT Safe.
*
* Returns: A result code indicating if the connection worked or
* what went wrong.
*/
GstPadLinkReturn
gst_pad_link_full (GstPad * srcpad, GstPad * sinkpad, GstPadLinkCheck flags)
{
GstPadLinkReturn result;
GstElement *parent;
GstPadLinkFunction srcfunc, sinkfunc;
g_return_val_if_fail (GST_IS_PAD (srcpad), GST_PAD_LINK_REFUSED);
g_return_val_if_fail (GST_PAD_IS_SRC (srcpad), GST_PAD_LINK_WRONG_DIRECTION);
g_return_val_if_fail (GST_IS_PAD (sinkpad), GST_PAD_LINK_REFUSED);
g_return_val_if_fail (GST_PAD_IS_SINK (sinkpad),
GST_PAD_LINK_WRONG_DIRECTION);
/* Notify the parent early. See gst_pad_unlink for details. */
if (G_LIKELY ((parent = GST_ELEMENT_CAST (gst_pad_get_parent (srcpad))))) {
if (G_LIKELY (GST_IS_ELEMENT (parent))) {
gst_element_post_message (parent,
gst_message_new_structure_change (GST_OBJECT_CAST (sinkpad),
GST_STRUCTURE_CHANGE_TYPE_PAD_LINK, parent, TRUE));
} else {
gst_object_unref (parent);
parent = NULL;
}
}
/* prepare will also lock the two pads */
result = gst_pad_link_prepare (srcpad, sinkpad, flags);
if (G_UNLIKELY (result != GST_PAD_LINK_OK)) {
GST_CAT_INFO (GST_CAT_PADS, "link between %s:%s and %s:%s failed: %s",
GST_DEBUG_PAD_NAME (srcpad), GST_DEBUG_PAD_NAME (sinkpad),
gst_pad_link_get_name (result));
goto done;
}
/* must set peers before calling the link function */
GST_PAD_PEER (srcpad) = sinkpad;
GST_PAD_PEER (sinkpad) = srcpad;
/* check events, when something is different, mark pending */
schedule_events (srcpad, sinkpad);
/* get the link functions */
srcfunc = GST_PAD_LINKFUNC (srcpad);
sinkfunc = GST_PAD_LINKFUNC (sinkpad);
if (G_UNLIKELY (srcfunc || sinkfunc)) {
/* custom link functions, execute them */
GST_OBJECT_UNLOCK (sinkpad);
GST_OBJECT_UNLOCK (srcpad);
if (srcfunc) {
GstObject *tmpparent;
ACQUIRE_PARENT (srcpad, tmpparent, no_parent);
/* this one will call the peer link function */
result = srcfunc (srcpad, tmpparent, sinkpad);
RELEASE_PARENT (tmpparent);
} else if (sinkfunc) {
GstObject *tmpparent;
ACQUIRE_PARENT (sinkpad, tmpparent, no_parent);
/* if no source link function, we need to call the sink link
* function ourselves. */
result = sinkfunc (sinkpad, tmpparent, srcpad);
RELEASE_PARENT (tmpparent);
}
no_parent:
GST_OBJECT_LOCK (srcpad);
GST_OBJECT_LOCK (sinkpad);
/* we released the lock, check if the same pads are linked still */
if (GST_PAD_PEER (srcpad) != sinkpad || GST_PAD_PEER (sinkpad) != srcpad)
goto concurrent_link;
if (G_UNLIKELY (result != GST_PAD_LINK_OK))
goto link_failed;
}
GST_OBJECT_UNLOCK (sinkpad);
GST_OBJECT_UNLOCK (srcpad);
/* fire off a signal to each of the pads telling them
* that they've been linked */
g_signal_emit (srcpad, gst_pad_signals[PAD_LINKED], 0, sinkpad);
g_signal_emit (sinkpad, gst_pad_signals[PAD_LINKED], 0, srcpad);
GST_CAT_INFO (GST_CAT_PADS, "linked %s:%s and %s:%s, successful",
GST_DEBUG_PAD_NAME (srcpad), GST_DEBUG_PAD_NAME (sinkpad));
gst_pad_send_event (srcpad, gst_event_new_reconfigure ());
done:
if (G_LIKELY (parent)) {
gst_element_post_message (parent,
gst_message_new_structure_change (GST_OBJECT_CAST (sinkpad),
GST_STRUCTURE_CHANGE_TYPE_PAD_LINK, parent, FALSE));
gst_object_unref (parent);
}
return result;
/* ERRORS */
concurrent_link:
{
GST_CAT_INFO (GST_CAT_PADS, "concurrent link between %s:%s and %s:%s",
GST_DEBUG_PAD_NAME (srcpad), GST_DEBUG_PAD_NAME (sinkpad));
GST_OBJECT_UNLOCK (sinkpad);
GST_OBJECT_UNLOCK (srcpad);
/* The other link operation succeeded first */
result = GST_PAD_LINK_WAS_LINKED;
goto done;
}
link_failed:
{
GST_CAT_INFO (GST_CAT_PADS, "link between %s:%s and %s:%s failed: %s",
GST_DEBUG_PAD_NAME (srcpad), GST_DEBUG_PAD_NAME (sinkpad),
gst_pad_link_get_name (result));
GST_PAD_PEER (srcpad) = NULL;
GST_PAD_PEER (sinkpad) = NULL;
GST_OBJECT_UNLOCK (sinkpad);
GST_OBJECT_UNLOCK (srcpad);
goto done;
}
}
/**
* gst_pad_link:
* @srcpad: the source #GstPad to link.
* @sinkpad: the sink #GstPad to link.
*
* Links the source pad and the sink pad.
*
* Returns: A result code indicating if the connection worked or
* what went wrong.
*
* MT Safe.
*/
GstPadLinkReturn
gst_pad_link (GstPad * srcpad, GstPad * sinkpad)
{
return gst_pad_link_full (srcpad, sinkpad, GST_PAD_LINK_CHECK_DEFAULT);
}
static void
gst_pad_set_pad_template (GstPad * pad, GstPadTemplate * templ)
{
GstPadTemplate **template_p;
/* this function would need checks if it weren't static */
GST_OBJECT_LOCK (pad);
template_p = &pad->padtemplate;
gst_object_replace ((GstObject **) template_p, (GstObject *) templ);
GST_OBJECT_UNLOCK (pad);
if (templ)
gst_pad_template_pad_created (templ, pad);
}
/**
* gst_pad_get_pad_template:
* @pad: a #GstPad.
*
* Gets the template for @pad.
*
* Returns: (transfer full) (nullable): the #GstPadTemplate from which
* this pad was instantiated, or %NULL if this pad has no
* template. Unref after usage.
*/
GstPadTemplate *
gst_pad_get_pad_template (GstPad * pad)
{
GstPadTemplate *templ;
g_return_val_if_fail (GST_IS_PAD (pad), NULL);
templ = GST_PAD_PAD_TEMPLATE (pad);
return (templ ? gst_object_ref (templ) : NULL);
}
/**
* gst_pad_has_current_caps:
* @pad: a #GstPad to check
*
* Check if @pad has caps set on it with a #GST_EVENT_CAPS event.
*
* Returns: %TRUE when @pad has caps associated with it.
*/
gboolean
gst_pad_has_current_caps (GstPad * pad)
{
gboolean result;
GstCaps *caps;
g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
GST_OBJECT_LOCK (pad);
caps = get_pad_caps (pad);
GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad,
"check current pad caps %" GST_PTR_FORMAT, caps);
result = (caps != NULL);
GST_OBJECT_UNLOCK (pad);
return result;
}
/**
* gst_pad_get_current_caps:
* @pad: a #GstPad to get the current capabilities of.
*
* Gets the capabilities currently configured on @pad with the last
* #GST_EVENT_CAPS event.
*
* Returns: the current caps of the pad with incremented ref-count.
*/
GstCaps *
gst_pad_get_current_caps (GstPad * pad)
{
GstCaps *result;
g_return_val_if_fail (GST_IS_PAD (pad), NULL);
GST_OBJECT_LOCK (pad);
if ((result = get_pad_caps (pad)))
gst_caps_ref (result);
GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad,
"get current pad caps %" GST_PTR_FORMAT, result);
GST_OBJECT_UNLOCK (pad);
return result;
}
/**
* gst_pad_get_pad_template_caps:
* @pad: a #GstPad to get the template capabilities from.
*
* Gets the capabilities for @pad's template.
*
* Returns: (transfer full): the #GstCaps of this pad template.
* Unref after usage.
*/
GstCaps *
gst_pad_get_pad_template_caps (GstPad * pad)
{
g_return_val_if_fail (GST_IS_PAD (pad), NULL);
if (GST_PAD_PAD_TEMPLATE (pad))
return gst_pad_template_get_caps (GST_PAD_PAD_TEMPLATE (pad));
return gst_caps_ref (GST_CAPS_ANY);
}
/**
* gst_pad_get_peer:
* @pad: a #GstPad to get the peer of.
*
* Gets the peer of @pad. This function refs the peer pad so
* you need to unref it after use.
*
* Returns: (transfer full): the peer #GstPad. Unref after usage.
*
* MT safe.
*/
GstPad *
gst_pad_get_peer (GstPad * pad)
{
GstPad *result;
g_return_val_if_fail (GST_IS_PAD (pad), NULL);
GST_OBJECT_LOCK (pad);
result = GST_PAD_PEER (pad);
if (result)
gst_object_ref (result);
GST_OBJECT_UNLOCK (pad);
return result;
}
/**
* gst_pad_get_allowed_caps:
* @pad: a #GstPad.
*
* Gets the capabilities of the allowed media types that can flow through
* @pad and its peer.
*
* The allowed capabilities is calculated as the intersection of the results of
* calling gst_pad_query_caps() on @pad and its peer. The caller owns a reference
* on the resulting caps.
*
* Returns: (transfer full) (nullable): the allowed #GstCaps of the
* pad link. Unref the caps when you no longer need it. This
* function returns %NULL when @pad has no peer.
*
* MT safe.
*/
GstCaps *
gst_pad_get_allowed_caps (GstPad * pad)
{
GstCaps *mycaps;
GstCaps *caps;
GstPad *peer;
g_return_val_if_fail (GST_IS_PAD (pad), NULL);
GST_OBJECT_LOCK (pad);
peer = GST_PAD_PEER (pad);
if (G_UNLIKELY (peer == NULL))
goto no_peer;
GST_CAT_DEBUG_OBJECT (GST_CAT_PROPERTIES, pad, "getting allowed caps");
gst_object_ref (peer);
GST_OBJECT_UNLOCK (pad);
mycaps = gst_pad_query_caps (pad, NULL);
caps = gst_pad_query_caps (peer, mycaps);
gst_object_unref (peer);
gst_caps_unref (mycaps);
GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad, "allowed caps %" GST_PTR_FORMAT,
caps);
return caps;
no_peer:
{
GST_CAT_DEBUG_OBJECT (GST_CAT_PROPERTIES, pad, "no peer");
GST_OBJECT_UNLOCK (pad);
return NULL;
}
}
/**
* gst_pad_iterate_internal_links_default:
* @pad: the #GstPad to get the internal links of.
* @parent: (allow-none): the parent of @pad or %NULL
*
* Iterate the list of pads to which the given pad is linked to inside of
* the parent element.
* This is the default handler, and thus returns an iterator of all of the
* pads inside the parent element with opposite direction.
*
* The caller must free this iterator after use with gst_iterator_free().
*
* Returns: (nullable): a #GstIterator of #GstPad, or %NULL if @pad
* has no parent. Unref each returned pad with gst_object_unref().
*/
GstIterator *
gst_pad_iterate_internal_links_default (GstPad * pad, GstObject * parent)
{
GstIterator *res;
GList **padlist;
guint32 *cookie;
GMutex *lock;
gpointer owner;
GstElement *eparent;
g_return_val_if_fail (GST_IS_PAD (pad), NULL);
if (parent != NULL && GST_IS_ELEMENT (parent)) {
eparent = GST_ELEMENT_CAST (gst_object_ref (parent));
} else {
GST_OBJECT_LOCK (pad);
eparent = GST_PAD_PARENT (pad);
if (!eparent || !GST_IS_ELEMENT (eparent))
goto no_parent;
gst_object_ref (eparent);
GST_OBJECT_UNLOCK (pad);
}
if (pad->direction == GST_PAD_SRC)
padlist = &eparent->sinkpads;
else
padlist = &eparent->srcpads;
GST_DEBUG_OBJECT (pad, "Making iterator");
cookie = &eparent->pads_cookie;
owner = eparent;
lock = GST_OBJECT_GET_LOCK (eparent);
res = gst_iterator_new_list (GST_TYPE_PAD,
lock, cookie, padlist, (GObject *) owner, NULL);
gst_object_unref (owner);
return res;
/* ERRORS */
no_parent:
{
GST_OBJECT_UNLOCK (pad);
GST_DEBUG_OBJECT (pad, "no parent element");
return NULL;
}
}
/**
* gst_pad_iterate_internal_links:
* @pad: the GstPad to get the internal links of.
*
* Gets an iterator for the pads to which the given pad is linked to inside
* of the parent element.
*
* Each #GstPad element yielded by the iterator will have its refcount increased,
* so unref after use.
*
* Free-function: gst_iterator_free
*
* Returns: (transfer full) (nullable): a new #GstIterator of #GstPad
* or %NULL when the pad does not have an iterator function
* configured. Use gst_iterator_free() after usage.
*/
GstIterator *
gst_pad_iterate_internal_links (GstPad * pad)
{
GstIterator *res = NULL;
GstObject *parent;
g_return_val_if_fail (GST_IS_PAD (pad), NULL);
GST_OBJECT_LOCK (pad);
ACQUIRE_PARENT (pad, parent, no_parent);
GST_OBJECT_UNLOCK (pad);
if (GST_PAD_ITERINTLINKFUNC (pad))
res = GST_PAD_ITERINTLINKFUNC (pad) (pad, parent);
RELEASE_PARENT (parent);
return res;
/* ERRORS */
no_parent:
{
GST_DEBUG_OBJECT (pad, "no parent");
GST_OBJECT_UNLOCK (pad);
return NULL;
}
}
/**
* gst_pad_forward:
* @pad: a #GstPad
* @forward: (scope call): a #GstPadForwardFunction
* @user_data: user data passed to @forward
*
* Calls @forward for all internally linked pads of @pad. This function deals with
* dynamically changing internal pads and will make sure that the @forward
* function is only called once for each pad.
*
* When @forward returns %TRUE, no further pads will be processed.
*
* Returns: %TRUE if one of the dispatcher functions returned %TRUE.
*/
gboolean
gst_pad_forward (GstPad * pad, GstPadForwardFunction forward,
gpointer user_data)
{
gboolean result = FALSE;
GstIterator *iter;
gboolean done = FALSE;
GValue item = { 0, };
GList *pushed_pads = NULL;
iter = gst_pad_iterate_internal_links (pad);
if (!iter)
goto no_iter;
while (!done) {
switch (gst_iterator_next (iter, &item)) {
case GST_ITERATOR_OK:
{
GstPad *intpad;
intpad = g_value_get_object (&item);
/* if already pushed, skip. FIXME, find something faster to tag pads */
if (intpad == NULL || g_list_find (pushed_pads, intpad)) {
g_value_reset (&item);
break;
}
GST_LOG_OBJECT (pad, "calling forward function on pad %s:%s",
GST_DEBUG_PAD_NAME (intpad));
done = result = forward (intpad, user_data);
pushed_pads = g_list_prepend (pushed_pads, intpad);
g_value_reset (&item);
break;
}
case GST_ITERATOR_RESYNC:
/* We don't reset the result here because we don't push the event
* again on pads that got the event already and because we need
* to consider the result of the previous pushes */
gst_iterator_resync (iter);
break;
case GST_ITERATOR_ERROR:
GST_ERROR_OBJECT (pad, "Could not iterate over internally linked pads");
done = TRUE;
break;
case GST_ITERATOR_DONE:
done = TRUE;
break;
}
}
g_value_unset (&item);
gst_iterator_free (iter);
g_list_free (pushed_pads);
no_iter:
return result;
}
typedef struct
{
GstEvent *event;
gboolean result;
gboolean dispatched;
} EventData;
static gboolean
event_forward_func (GstPad * pad, EventData * data)
{
/* for each pad we send to, we should ref the event; it's up
* to downstream to unref again when handled. */
GST_LOG_OBJECT (pad, "Reffing and pushing event %p (%s) to %s:%s",
data->event, GST_EVENT_TYPE_NAME (data->event), GST_DEBUG_PAD_NAME (pad));
data->result |= gst_pad_push_event (pad, gst_event_ref (data->event));
data->dispatched = TRUE;
/* don't stop */
return FALSE;
}
/**
* gst_pad_event_default:
* @pad: a #GstPad to call the default event handler on.
* @parent: (allow-none): the parent of @pad or %NULL
* @event: (transfer full): the #GstEvent to handle.
*
* Invokes the default event handler for the given pad.
*
* The EOS event will pause the task associated with @pad before it is forwarded
* to all internally linked pads,
*
* The event is sent to all pads internally linked to @pad. This function
* takes ownership of @event.
*
* Returns: %TRUE if the event was sent successfully.
*/
gboolean
gst_pad_event_default (GstPad * pad, GstObject * parent, GstEvent * event)
{
gboolean result, forward = TRUE;
g_return_val_if_fail (GST_IS_PAD (pad), FALSE);
g_return_val_if_fail (event != NULL, FALSE);
GST_LOG_OBJECT (pad, "default event handler for event %" GST_PTR_FORMAT,
event);
switch (GST_EVENT_TYPE (event)) {
case GST_EVENT_CAPS:
forward = GST_PAD_IS_PROXY_CAPS (pad);
result = TRUE;
break;
default:
break;
}
if (forward) {
EventData data;
data.event = event;
data.dispatched = FALSE;
data.result = FALSE;
gst_pad_forward (pad, (GstPadForwardFunction) event_forward_func, &data);
/* for sinkpads without a parent element or without internal links, nothing
* will be dispatched but we still want to return TRUE. */
if (data.dispatched)
result = data.result;
else
result = TRUE;
}
gst_event_unref (event);
return result;
}
/* Default accept caps implementation just checks against
* the allowed caps for the pad */
static gboolean
gst_pad_query_accept_caps_default (GstPad * pad, GstQuery * query)
{
/* get the caps and see if it intersects to something not empty */
GstCaps *caps, *allowed;
gboolean result;
GST_DEBUG_OBJECT (pad, "query accept-caps %" GST_PTR_FORMAT, query);
/* first forward the query to internally linked pads when we are dealing with
* a PROXY CAPS */
if (GST_PAD_IS_PROXY_CAPS (pad)) {
if ((result = gst_pad_proxy_query_accept_caps (pad, query))) {
goto done;
}
}
GST_CAT_DEBUG_OBJECT (GST_CAT_PERFORMANCE, pad,
"fallback ACCEPT_CAPS query, consider implementing a specialized version");
gst_query_parse_accept_caps (query, &caps);
allowed = gst_pad_query_caps (pad, caps);
if (allowed) {
if (GST_PAD_IS_ACCEPT_INTERSECT (pad)) {
GST_DEBUG_OBJECT (pad,
"allowed caps intersect %" GST_PTR_FORMAT ", caps %" GST_PTR_FORMAT,
allowed, caps);
result = gst_caps_can_intersect (caps, allowed);
} else {
GST_DEBUG_OBJECT (pad, "allowed caps subset %" GST_PTR_FORMAT ", caps %"
GST_PTR_FORMAT, allowed, caps);
result = gst_caps_is_subset (caps, allowed);
}
gst_caps_unref (allowed);
} else {
GST_DEBUG_OBJECT (pad, "no compatible caps allowed on the pad");
result = FALSE;
}
gst_query_set_accept_caps_result (query, result);
done:
return TRUE;
}
/* Default caps implementation */
static gboolean
gst_pad_query_caps_default (GstPad * pad, GstQuery * query)
{
GstCaps *result = NULL, *filter;
GstPadTemplate *templ;
gboolean fixed_caps;
GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad, "query caps %" GST_PTR_FORMAT,
query);
/* first try to proxy if we must */
if (GST_PAD_IS_PROXY_CAPS (pad)) {
if ((gst_pad_proxy_query_caps (pad, query))) {
goto done;
}
}
gst_query_parse_caps (query, &filter);
/* no proxy or it failed, do default handling */
fixed_caps = GST_PAD_IS_FIXED_CAPS (pad);
GST_OBJECT_LOCK (pad);
if (fixed_caps) {
/* fixed caps, try the negotiated caps first */
GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad, "fixed pad caps: trying pad caps");
if ((result = get_pad_caps (pad)))
goto filter_done_unlock;
}
if ((templ = GST_PAD_PAD_TEMPLATE (pad))) {
GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad, "trying pad template caps");
if ((result = GST_PAD_TEMPLATE_CAPS (templ)))
goto filter_done_unlock;
}
if (!fixed_caps) {
GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad,
"non-fixed pad caps: trying pad caps");
/* non fixed caps, try the negotiated caps */
if ((result = get_pad_caps (pad)))
goto filter_done_unlock;
}
/* this almost never happens */
GST_CAT_DEBUG_OBJECT (GST_CAT_CAPS, pad, "pad has no caps");
result = GST_CAPS_ANY;
filter_done_unlock:
GST_OBJECT_UNLOCK (pad);
/* run the filter on the result */
if (filter) {